With the improvement of the living environment of recent years, there is an increasing desire of the removal of odor. Such odor includes, for example, an. alkaline odor from ammonia, amine or the like, an acidic odor from a lower fatty acid or the like, a sulfur-containing compound odor from a mercaptan or the like, and a neutral odor from an ester, a ketone, or an aldehyde or the like. It is important to remove a wide variety of these odors having different physical properties. As methods of removing foul odor, there have been known a masking method, an ozone oxidation method, a drug neutralization method, a microbial degradation method, an adsorption method and the like (see, for example, “Atarashii Shoshu/dasshuzai to Gijutsu no Tenbo—Amenithi Shakai heno Apurouchi—(New Deodorant and Prospect for Technology—Approach to Amenity Society,” authored by ICS Co., Ltd., TORAY RESEARCH CENTER, Inc., published in September, 1994, p. 12-24).
However, each of the above-mentioned methods has some disadvantages. For example, the masking method cannot be said as a method of essentially removing an odor; ozone is handled in the ozone oxidation method, thereby necessitating that facilities be large-scaled; in the drug neutralization method, a substance to be treated is limited to a neutralizable substance, thereby making an odor to be treated by the method limited; and the microbial degradation method does not give an immediate effect. Further, these methods have a disadvantage in safety when applied to a human body.
On the other hand, the adsorption method is a convenient method of deodorization having an immediate effect and being highly safe. An activated carbon is widely used as an adsorbent. However, the method has some disadvantages that the activated carbon has low deodorizing ability against ammonia, and that cleanliness might be lost when applied to a human body because of its black color. White deodorants include zeolite and activated clay, but the deodorants fall shorter in their deodorizing ability than the activated carbon.
In addition, among the household foul odors, a sulfur-containing foul odor itself from a mercaptan or hydrogen sulfide has a very low threshold value, so that it is recognized as a strong foul odor even when contained in a very small amount. Especially, a foul odor component generated from excretions, kitchen garbage and the like is mostly occupied by the sulfur-containing foul odor. Therefore, one having a strong deodorizing power has been desired for these foul odors.